All Pumps Machinery Company Limited.

Reasons and Solutions for the Failure of Self-priming Pumps to Draw Water

  • Due to the poor sealing of the suction pipe of the self-priming pump, the self-priming pump has been in a state of emptying air and cannot suck water.


Solution: Check the sealing of the inlet pipe of the self-priming pump and repair the leaking points, such as welding and pipe joints, suspected of air leakage. For example, you can listen for air suction sounds by shutting down and approaching the pipe after running for about 5 minutes.


  • The self-priming pump that has been used for a period of time may not be able to suck water due to corrosion, wear, and leakage of the mechanical seal.


Solution: Replace the damaged parts to solve the problem.


  • Due to the presence of a large amount of debris in the transported liquid, the pipeline or even the pump body may be blocked, which can also cause the self-priming pump to not suck water.


Solution: Find the specific blockage point and clear the debris to solve the problem.


  • Due to the improper installation of the inlet pipe of the self-priming pump.


For example, the number of elbows should be controlled to 1-2 when there are too many elbows. It is better to use 45-degree elbows as much as possible. The diameter of the pipeline is not matched with the pump diameter, which can also cause the self-priming pump to not suck water.


  • After the first time the self-priming pump sucks up water, water must be poured in before it can be sucked up for the second time, indicating that air has entered the pump body of the self-priming pump. For example, if the outlet pipe of the self-priming pump is not equipped with a shut-off valve, water backflow will occur after stopping the machine, and air will be sucked into the pump body of the self-priming pump. Water needs to be poured in and exhausted to suck the water up next time.


The solution to this kind of self-priming pump not sucking water is to install a shut-off valve and ball valve at the outlet, and close the outlet valve before stopping the machine to solve the problem.


  • The self-priming pump exceeds the allowable suction height during actual installation and use. It is recommended to replace it with a self-priming pump with a higher self-priming height or use a submersible pump.


As one of the self priming centrifugal pump manufacturers, ALL PUMPS MACHINERY adopts the most advanced technology to manufacture and can fully interchange with other several world-renowned brands of solid handling self-priming debris pumps, heavy-duty slurry pumps, sand pumps, diaphragm pumps, and centrifugal pumps. Their design allows easy and fast access to internal parts for cleaning and easy handling. Welcome to consult.